3.8 Swap Thread

**Bring380GT** · 05-26-2010, 07:33 AM

Good info! all though I'm running a 74 engine right now with out a tune and it does not run lean it runs a 13.3 most of the time along with some richer levels on the wideband so..

**skyy406** · 05-27-2010, 09:22 PM

Update today.

Let me just say. The engine hoist stabilizer is an absolute must have. I was able to tilt the engine/transmission to perfection. Literally was able to drop the motor in, in about 4 minutes once it was in the air.

Amazing useful tool. I have to buy a transmission jack as I need to be able to rotate the engine slightly and also tilt it down slightly. Did a pretty good job though centering it with some blocks of wood though for now until I pick one up.

I am amazed how much smaller the a543 really is in the engine bay. Looks great in there like it was made for this engine bay. Much more so than the a604.

Next step is making the mounts.

I have a pretty good idea where to make 2 of the mounts for the transmission using existing threaded holes. Except the front transmission mount. The a604 has some tapped holes right in the side of the bell housing and lots of extra aluminum to support weight. The a543 does not. I am a little worried what to do for this mount. Any ideas or suggestions would be great.

a604

a543

Look at this pic. Where is it red is where the bolt holes should be. There looks to be a weak point in my opinion with that "hole" or gap between the outer bell housing and inner bell housing. I sure do wish someone with an a543 already in their car would take some pics for me of that front mount ;)

Here's my idea for the rear mount. Basically I will be using the stock transmission mount and bolting or welding a metal extension to the bracket. I will unbolt 2 large bolts from the transmission (looks like differential cover) and then sandwich the metal bracket between longer bolts. I'm using 1/2" thick solid steel for the bracket. Should be overly strong enough. It will be shaped like a 7 of sorts.

Before:

After:

The front mount also seems to be an easy mount.

There are 2 threaded holes right on top of the transmission- right below where the main transmission mount is located at:

And many hours of diligent searching I found the mount made by DMS right here on ASEC. Exactly what I was going to do anyway. Weld a bracket to an existing mount that I got from an Eclipse.

This bracket that goes from the engine to the transmission sure has been a PITA. I can't seem to get the starter to really sit flush against the a543. Nearly flush but not perfect. I know all I have to do is grind more metal off, its just time consuming- this metal is very hard.

**Bring380GT** · 05-28-2010, 06:23 AM

Wow man! looking good

**jimmy_o2** · 05-28-2010, 07:44 AM

too good

**Bring380GT** · 05-28-2010, 08:58 AM

With alot of thinking and SPD's Info/build and this guys build I'm going to buy a 6G75 and hope for some good numbers with my current 74 mods and a tune, also I think I'm going to have to have to get that intake manifold Boostzealot had made(seeing that these heads flow so well), already have the lower part of the Xg350 mani and the VH45 throttle body, also think I might pick up RPW headers for it too!

**skyy406** · 05-28-2010, 09:38 AM

Originally Posted by Bring350GT

With alot of thinking and SPK's Info/build and this guys build I'm going to buy a 6G75 and hope for some good numbers with my current 74 mods and a tune, also I think I'm going to have to have to get that intake manifold Boostzealot had made(seeing that these heads flow so well), already have the lower part of the Xg350 mani and the VH45 throttle body, also think I might pick up RPW headers for it too!

Yeah! Glad to hear it!!!!

**Bring380GT** · 05-28-2010, 09:43 AM

Originally Posted by skyy406

Yeah! Glad to hear it!!!!

Inspiration both ways

**M-Rod** · 05-28-2010, 08:10 PM

Originally Posted by Bring350GT

Inspiration both ways

Agreed. Seeing things happen makes me want to get off my ass and step up to the big displacement group.

**skyy406** · 06-11-2010, 09:33 AM

Well after a lot of planning a ton of thinking. I have decided to utilize the factory mount on the passenger side and I made a Bracket that will be bolted to the Mount and then bolted to the transmission.

I decided that I wanted to use as much factory equipment as possible from here on out. I want to try and limit the amount of custom parts needed that I couldn't make myself. And being that my welder cannot weld aluminum that thick- I didn't really have many options. I bought hardened studs that will be inserted into bolt holes that I will drill out tomorrow or Sunday for the mount. I also have a very clever Idea for the rear mount.

After looking over pictures of the 5-speed turbo venge (DMS did not use a bobble-strut) I can duplicate their mount but make it much more simple. After the main transmission mount is done- i'll work on the rear mount.

Also I have yet to gusset the mount which I will do also.

Here's the factory mount:

Here's the bracket. It's made out of 1/4" solid steel. I still have to trim it a bit- and also drill all the holes. But I wanted you all to see what I am up to.

Here it is just laying there so you can get an idea of what I am doing with it.

I also encountered a problem. First off I couldn't fit 1/4" steel between the tranny mount and the transmission without modifying the transmission. So I decided to create the space. I made a 1/4" spacer on the passenger's side main engine mount which lowered the entire engine 1/4"- fit's much better now.

Welding by the way... is A LOT OF FUN!!!

**Galantfan88** · 06-11-2010, 10:35 AM

This is some really good stuff here guys, and SPK is a freakin awesome guy. He takes time to really give out some good info and help others with projects that hasnt even been done like the 6g75 swap. This makes me really want to get the v6 G and do a project like this. Keep up the good work man I hope everything turns out ok and SPK I can not wait to see that baby start up.

**skyy406** · 06-11-2010, 12:57 PM

Thanks for the props man! That's one of the main reasons I am posting my build to a bunch of different forums. You'd be surprised how members viewing my thread will get inspiration to get off their ass and do things they wanted to do anyway but were procrastinating.

**M-Rod** · 06-11-2010, 11:05 PM

Originally Posted by skyy406

Thanks for the props man! That's one of the main reasons I am posting my build to a bunch of different forums. You'd be surprised how members viewing my thread will get inspiration to get off their ass and do things they wanted to do anyway but were procrastinating.

No kidding! I think it was within a week of reading, I hammered out the 75 swap. Funny thing is I'm usually the world's largest procrastinator.

**skyy406** · 06-13-2010, 10:00 PM

Update

I still really can't get the bracket to sit completely flush with the tranny mount. It rubs on the transmission and I don't like that. I can't get the engine/trans completely perfectly level and I want to. I need to lower the engine about the thickness of a washer. So that's what I am going to do and see how that works.

I trimmed the bracket a lot today and also drilled the three 1/2" holes for the new studs. Those bolts that you see below are not the finished product those are just so I could mock everything up.

Also.

My welder doesn't seem to get hot enough. The welds aren't to my liking. I am not getting complete penetration through the 1/4" steel. My welder is completely capable of that and I know the problem. Every single outlet in the house I am doing the swap at are 10 amp outlets. I need at least 20amp to weld metal this thick. No biggie. I welded some gusset's onto the bracket for added strength and tomorrow the bracket will be welded by a shop- to keep my mind at ease.

I'll mock up the rear mount and then have it welded by the shop also as it will be made out of 1/2" steel in some areas. I didn't bother to clean up the welds as they will be re-welded and when they are done I'll smooth everything out and make it pretty. I think I'll paint the bracket when its finished too.

Test fit before trimming and gusset's:

This drill is amazing. With sharp bits it has enough torque to plow through the steel like butter.

**mrg7243** · 12-07-2010, 01:18 PM

http://www.club3g.com/forum/3g-eclip...c-avenger.html

Here is the guy's build thread over on club3g. He said he forgot about updating here, but it is an amazing build, and a great read.

**skyy406** · 04-08-2011, 12:57 AM

wow sorry for not updating the thread. Heres the newest pics. 3.8L is in. I rebuilt the A543. Mounts are solid, shifter works great- finishing up the wiring!

Oh boy that looks purdy!

My garage is starting to clean up a little bit now that im putting the car back together

Getting closer and closer every day guys!